1. Field of the Invention
The present invention relates to radiographic imaging, and more particularly to an opto-electro-mechanical scanning assembly for retrieving information from imaged photostimulable phosphor imaging plates, the scanner being portable and having an enhanced arrangement of scanning elements to significantly enhance the clarity of the scanned image.
2. Description of the Prior Art
Traditional x-ray imaging systems using silver-based films are being replaced by radiographic imaging systems using photostimulable phosphor imaging films or storage substrates, thereby eliminating the need for physical storage of the imaged film since digital retrieval of the image information includes input and computer storage permitting viewing of such information on a CRT tube assembly or the equivalent thereof. Additionally, such computer storage imaging information permits facile electronic transmission to any predetermined location obviating the physical transfer of imaged film. Such radiographic imaging further permits the erasure of the image from the photostimulable phosphor imaging film or storage substrate, and the subsequent reuse thereof.
In U.S. Pat. No. 5,874,744 to Goodman, et al., assigned to the same assignee as the present invention, herein incorporated by reference, there is disclosed a process and apparatus for processing radiographic information from an anisotropic storage phosphor screen including an opto-electro-mechanical assembly to achieve faster scan of an interrogating beam and including detector and computer assembly.
In U.S. Pat. No. 6,599,004 to Thoms, there is disclosed an apparatus for reading flexible storage films wherein the flexible storage film having image-wise projected information is positioned on a cylindrically-shaped surface and is caused to be linearly moved there over by transport assemblies while being interrogated or scanned via a slot by a light beam generated in a helical line in a continuous manner from a point disposed at the axis of the cylindrically-shaped surface thereby generating luminescence detected by one or more photomultiplier tubes.
The output signal of the photomultiplier is recorded together with the output signals of the position encoder, thereby obtaining a digital electronic image of the x-ray image previously formed on the storage film in the form of exited metastable color centers of the phosphor particles. Such image is then further processed electronically in view of changing the scale of reproduction, emphasizing details, improving the signal/noise ratio, etc. The resulting image may be put into an archive in its original and/or digitally processed form requiring very little space.
Photostimulable phosphor imagining plate scanners of the type thus described are used in dental operatories, medical offices, and veterinary clinics. In normal use, due to the size of the scanner, it is typically positioned centralized within the dental, medical or veterinary clinic for the processing of imaged photostimulable phosphor imaging plates. There has been a need for a truly portable photostimulable phosphor imaging plate scanner of a reduced size, but which does not compromise the quality of the digitized image. Such portable scanners would have a use as a chair side unit in dental or medical offices, or a truly portable unit for veterinary use when attending to animals in their natural locale, and not in the veterinary operatory. Portable units of the type described would also have application in non-destructive testing and industrial X-ray situations wherein the portability of the unit allows its transport to locations previously unavailable or hostile to scanner use.
Applicant's opto-electro-mechanical scanning assembly of the present invention provides this portability need by not only reducing the size and number of elements within the scanner, but by also incorporating novel and unique design arrangements of those elements in order to provide for a portable unit that does not compromise the digitized image. Moreover, certain of the novel and unique design arrangements when applied to larger non-portable scanners improve the function and operation of such scanners and the clarity of their digital images.